Dione's thin oxygen exosphere

2 March 2012

Dione is a moon of Saturn, discovered in 1684 by the Italian
astronomer Giovanni Cassini. Over 300 years later, planetary
scientists including Andrew Coates and Geraint Jones from MSSL-UCL,
have discovered that Dione has a weak exosphere near its surface (at
planets with denser atmospheres, the exosphere is the outermost
layer of its atmosphere). This work was featured on BBC News Online and is also the feature of a science nugget on the planetary science group website.